Variable flame type gas burner



Oct. 27, 1964 s. BLOOM 3,154,134

VARIABLE FLAME TYPE GAS BURNER Filed April 30, 1954 56 i fii ,9

38 zswl ll ll ll l II A 40 5| 46 4 11111111111/1/11111 1 1!! I 111111111/ [III] I IJJ 4 8 FREDERICK s. BLOOM United States Patent 3,154,134VARIABLE FLAME TYPE GAS BURNER Frederick S. Bloom, Mount LebanonTownship, Allegheny County, Pa. Bloom Engineering Company Inc, 857 W.North Ave, North Side, Pittsburgh 33, Pa.) Filed Apr. 30, M54, Ser. No.426,679 Claims. ((31. 158-109) This invention relates to a noveladjustable burner construction whereby the characteristics of flameproduced thereby may be varied. More particularly, this inventionpertains to new industrial burners particularly useful, for example, inthe heating of slabs and billets in the steel industry, in which burnersand adjustment may be made for varying flame character between flamewhich is relatively long and luminous, and, flame which is relativelyshort and clear for given conditions of fuel and combusttion air supply.

In the design and construction of furnaces in the steel industry, as anexample, for heating slabs or billets, particular burners haveheretofore been extensively provided which yield the so-called luminousor long flame of relatively high radiating character. While such burnersare highly satisfactory in many applications, particularly in thosecases where the burner has been constructed on a custom-made basis forthe particular installation, the fact remains that such burners arerelatively inflexible. Hence, if need should arise at a given fuelcapacity for a relatively shorter flame or a relatively clearer flame,it has been necessary to modify or replace the burners in thatparticular furnace. Further, any such modification itself constituted arelatively inflexible alteration, a significant difiiculty especially inview of the relative unpredictability of furnace action in many casesuntil actually tried out. Heretofore, also, industrial burners having aluminosity of flame character built into them have tended to be slowerburning than desired for a given luminosity and, moreover, there hasalso tended to be a carbon or smoke problem present with the flame inmany such installations. Still further, at relatively low turndown offuel, generally with fuel gas like coke oven gas or natural gas in suchprior luminous flame burners, and combustion air, there has been atendency in numerous installations for the flame to lick the furnacewall as it exited from the port block and sometimes, to move too slowly.

The foregoing and other difficulties are overcome by the presentinvention. By means of my invention, new burner equipment is providedand is adjustable so that in each such new burner the flame charactermay be varied between a flame which is relatively long and luminous,and, a flame which is relatively short and clear. Further, that novelvariation is obtainable without significant alteration in a given burnerof either the pressure of the fuel, such as a fuel gas, or of thecombustion air. Moreover, the fuel gas is never starved for combustionair in my new construction and those flames which are luminous are morebrightly luminous and in all cases burn completely without carbon orsmoke residue. The lack of any necessity to vary the respective fuel andair pressures also means that a particular furnace using my inventionmay have some of the burners on luminous operation with others of theburners on semi-luminous or on clear flame operation as occasion demandsto control in the furnace the place of occurrence of flame temperaturepeak, the flame and heat pattern itself, the spread of temperaturebetween the inside furnace wall and the work being heated, and otherelements of possible controlling significance in obtaining a furnace andburner operation of highest efficiency. It may also be remarked that atlow turndown with my new burner construction, even on an operation ofmaximum luminosity, the flame produced does not lick up the adjacentfurnace wall but proceeds ice relatively directly and quickly into thefurnace interior for maximum effectiveness.

Other and further objects and advantages of my invention will beapparent from the following description and from the accompanyingdrawings, which are illustrative only, in which FIGURE 1 is a view incross section of an embodiment of my invention showing one adjustmentposition and a possible mounting arrangement;

FIGURE 2 is a view of the embodiment of FIGURE 1 in less complete crosssection in another adjustment position;

FIGURE 3 is a front view of my new burner, on a more reduced scale,taken along line IlI--III of FIGURE 2;

FIGURE 4 is a view in section of my new burner taken along line IV1V ofFIGURE 2; and

FIGURE 5 is a view in section of the nozzle element in the illustratedembodiment, taken along line VV of FIGURE 2.

Referring to the drawings, my new burner may comprise an air body orhousing 11 having a mounting flange 12 to enable burner It) to bereadily mounted in a Wall 13 of a furnace. Such furnace may include sucha vertical wall 13 of refractory within a metal shell 14 to which a portblock plate 15 is readily attachable by the employment of studs 16 andnuts 17. A refractory port block 18 may be provided so as to fit in anopening in wall 13, the aforesaid port block having a flaring port 19extending from the face 20 of port block 18 to a counterrecess 21. Acylindrical projection 22 on body 11 may be provided to fit recess 21when new burner 10 is in mounting position. Burner 10 may be aflixed tostuds 23 secured by welding or otherwise to port block plate 15,mounting flange 12 being held on such studs, for example, by nuts 24. Somounted, new burner 10 discharges fuel, such as natural or manufacturedor process reaction gas, with combustion air toward port 19 in thecourse of a combustion operation in the direction of the flare of theport 19 so that flame of a desired characteristic passes into thefurnace interior 25 for the heating service to be performed by my newburner 10.

Air body or housing 11 is tubular, and cylindrical in the illustratedembodiment, with a slight divergence in a forward direction towardfurnace interior 25, although such divergence is not necessary andhousing 11 in many cases will be made as a straight tubular combustionair body. A light-off hole 26 may also be provided adjacent the forwardend of body 11 through which ignition of the combustible mixture may beeffected upon initiation of a burner operation utilizing burner 10.Normally a plug 27 closes the outer end of hole 26. As shown further,air body 11 is cast with an annular combustion air chamber 28 adjacentthe back thereof, that chamber 23 having outer wall 29 terminating in aconduit 30 with a fastening flange 31 to define a combustion air entry32.. A combustion air header 33 is fastened to conduit 3% and suppliescombustion air therethrough to conduit 34 and new burner 10 in thedesired volume and at the desired pressure and temperature. Thetemperature of such combustion air may be ambient or room temperature,or in some cases, the combustion air may be preheated as will be wellunderstood by those skilled in the art to whom this invention isdisclosed.

A back plate 34 may be provided and fastened by bolts 35 to the rear ofwall l to close annular chamber 28. Inner wall 36 of chamber 28 may bean integral part of body 11 and extend rearwardly to a rear edge 37.Back plate 34 may be provided with forwardly extending radial ribs 38 ina cylindrical arrangement which, when back plate 34 is in mountedposition, is positioned close to rear edge 37 generally leaving a shortspace 39. Thereby, combustion air from header 33 may readily flowthrough the radial interstices 3&1 between the ribs 38 and through anyspace 39 into the interior 4 d of air body 11 from around the entireperiphery of inner wall as, giving relatively uniform distribution ofair going through the burner parallel to the longitudinal axis of newburner 10.

Back plate 34 may be provided with spaced annular bosses 41 and 42, theouter boss 41 being tapped, for example, for connection to a pipe 43through which a gas, which is suitable for use as a fuel, may flow inthe direction shown by the arrow 44. The inner or forward boss 42 may betapped to enable a tubular nozzle 45 to be screwed into boss 42.Thereby, hollow nozzle d in effect affords a continuation to pipe 43 toconduct the fluid fuel toward a nozzle tip 46 at the forward or innerend of nozzle 45. Nozzle tip 4-6 may be provided with radially extendingoutlet passages 47 whereby the fuel is discharged at an angle to theaxis of new burner It? into combustion air flowing toward interior 25through air body 11 between the inside 43 thereof and the outside ofnozzle 45, effecting a combustible mixture for a burning operation andyielding a flame to heat work in the furnace interior 25. Suitablecontrols, not illustrated, will usually be provided so that as thevolume of fuel is varied, the volume of combustion air fed to new burnerwill correspondingly be varied to maintain whatever fuel-combustion airratio is selected in advance for the particular operation utilizing mynew burner.

A collar 49 is provided in new burner fit to lit around the outside ofnozzle 45, in slidable relation thereto. A lug 50 on collar 49 enablesit to be moved back and forth to any adjustment position within burnerllt'l between, in the illustrated embodiment, extreme positionsrespectively shown in FIGURES l and 2. A rod 51 may be secured to lug 50by a pin 52, an adjustment knob 53 being secured to the other end of rod51. Rod 51 may pass through an opening 54 in back plate 34 which openingis of lesser diameter than the diameter of a spacing sleeve 55 throughwhich rod 51 may also extend. A set screw 56 may be provided to lock rod51 in either extreme position or in any intermediate position betweenextreme adjustment positions of collar 49. The forward or inner extremeadjustment position of collar 49 may be fixed by the employment of anabutment nut 57 to stop against the back of back plate 34 as shown inFIGURE 1. Conversely, the outer or rearward extreme adjustment positionof collar 4-9 may be fixed by providing sleeve 55 with a suitablepredetermined length which is operative as is shown in FIGURE 2 when therear extreme adjustment position is selected.

A transversely extending plate 58 constitutes, in the illustratedembodiment, an imperforate discoidal flange forming a part of collar 49.Plate 58 has an inner or forward face 5% and a peripheral edge fit}spaced from the inside 48 of air body 11. In general, the annular areabetween peripheral edge tit) and inside 48 of air body 11 is at least asgreat as the area that is bounded by the peripheral edge 69 of flange58.

I have found that a new burner construction, such as is illustrated anddescribed herein for use with a combustible gas, enables thecharacteristic of the flame produced by that burner to be varied atwill. Thus, in the extreme rear or outward adjustment position shown inFIGURE 2, for the illustrated embodiment, the flame produced by thatburner 10 in operation will be relatively long and luminous. Even at lowturndown when the capacity of the burner is reduced by a reduction ofthe quantity of fuel and combustion air fed thereto, the flame will notlick up the face 2d of port block 18 and of wall 13, but will move oninto the furnace in the same direction that it does when the fuel andair are turned up. Still further, I have found that carbon particles andsmoke are significantly absent from flame produced by the new burnereven when the burner is adjusted so that the flame is luminous, acircumstance which may permit of shorter and therefore less expensivefurnace construction, and, the yielding of greater heat to the work.When in a luminous flame position, my new burner still burns relativelyfast rather than acting as a so-called lazy flame.

On the other hand, with the transversely extending plate in the extremeforward or inward adjustment position shown in FIGURE 1, the flameproduced by new burner fill in operation will be relatively clear and arelatively shorter flame. In other words, in more forward positions ofplate 5%, my new burner produces a relatively biuer, faster burning andshorter flame than it does with flange 58 in adjustment positionsfarther away from nozzle tip 46. A significant consequence of my newconstruction is that a furnace provided with my new burners can befurnished with length and kind of flame desired and, in addition, a heatpattern that is most desirable for the particular service in which thatfurnace is engaged at the time then being. Since furnace constructioninvolves certain imponderables, the flexibility and flame adjustmentcharacter of my new burners permits ready correction of any combustiondefects which might otherwise have shown up in such a furnace were it tohave been operated with conventional burners.

Thus, in using a plurality of my new burners in the wall or walls,including ceilings and floors, of a furnace, some of those burners maybe provided with the plate corresponding to flange 58 in an adjustmentposition such that the flame issuing therefrom is longer and moreluminous whereas in others of my new burners in that furnace, adifferent adjustment will be used to provide clearer and shorter flamesfor a joint cooperative flame character and heating effect suited to theparticular requirement at the time being. If and when a furnaceutilizing my new burners is scheduled for a somewhat different kind ofservice in heating work passed therethrough, my burners may bereadjusted as and to the extent required to readily and convenientlysuit the new flame and heating pattern that is optimum for the changedfurnace requirement. Between the extreme adjustment positions of thetransversely extending plate in one of my new burners, a flame characterin between the extreme clear flame and the extreme luminous flameconditions is obtainable. Hence, by means of my new construction and theadjustability thereof, a new burner may have whatever variation betweenclear and luminous flame and length of flame are desired in the range ofthe capacity of the new burner. Further and quite importantly,adjustments of my new burner to vary, at will, the flame condition andlength as recited herein, afford such flexibility without requiringmodification of the temperature or static pressure at which thecombustion air and fuel are respectively supplied.

In addition to gas fuels, other fluid fuels capable of acting with agaseous-like aspect may also be supplied through a pipe like pipe 43 toa nozzle like nozzle 45 in a burner constructed in accordance with thisinvention.

Thus, atomized oil in a so-called emulsion with a pressure atomizingfluid such as air or steam may be used in a new burner of thisinvention. Further, nozzle 45 may be replaced in a fluid pressureatomizer discharging a mixture of atomized oil and atomizing air, foreaxmple, at an angle to the longitudinal axis of the new burner incooperation with the other elements of my new construction for theachievement of advantages thereof. Indeed, various modifications inassembly and construction of structural elements may be made withoutdeparting from the spirit of my invention or the scope of the appendedclaims. In making my new burners, the portions exposed to sufficientheat will preferably be made of a suitable heat-resisting ferrous alloywhile the remaining portions of my new structure may be made of lessthermally resistant materials.

I claim:

1. In combination, in an adjustable burner, a tubular air body ofgenerally uniform cross section free from transverse constrictionadjacent its inward part, a cham ber adjacent the outer end of said airbody to receive and distribute substantially all of the combustion airuniformly to the inside of said body, a fuel nozzle extending axiallywithin said air body toward the inner end of said body, said nozzlehaving means to discharge at least a portion of the fuel transverselyadjacent said inner end, a transversely extending flange plate fittingaround said nozzle for sliding movement thereon between a positionadjacent the back of said discharge means and a position toward theouter end of said body, said flange plate having a peripheral edgesubstantially uniformly spaced from the inside of said body in anyoperative position of said flange plate such that in the plane of saidflange plate the annular area between said edge and said inside of saidbody is generally at least as great as the area within said periphery ofsaid flange plate, and means extending to the outside of said burner formoving said flange plate to a selected adjustment position within itsrange of movement, whereby said burner may be adjusted to vary a flameproduced therefrom from a relatively more luminous and longer flame whenthe inward face of said flange plate is away from said discharge means,to a relatively clearer and shorter flame when said face of said flangeplate is nearer to said discharge means.

2. In combination, in a fuel gas burner adapted to have its inner endextending toward a furnace interior, a fixed axially extending nozzle toconduct substantially all of said fuel, said nozzle having outlet meansadjacent said inner end adapted to discharge at least a portion of thefuel gas substantially transversely around the axis of said nozzle, .atransversely extending annular plate surrounding said nozzle inrelatively close fitting relation thereto and movable therealong througha substantial distance range, means extending to the outside of saidburner to move said plate to a selected adjustment position outwardly ofsaid outlet means and relative to said inner end of said burner for anyoperative position of said plate, tubular body means of substantiallyuniform internal cross section inclusive of the inner discharge endthereof for conducting substantially all of the combustion air for saidfuel substantially axially inwardly past the periphery of said plate,said inner discharge end being adjacent said outlet means, said tubularbody means surrounding said plate and being transversely spaced fromsaid periphery thereof in any operative position of said plate, andlimit means to prevent said plate being positioned inwardly of saidtubular body means, whereby the character of a flame provided by saidburner may be varied by axial movement of said plate relative to saidoutlet means.

3. In combination, in .a burner for a gaseous fuel, an axially extendingtubular body, a hollow nozzle extending axially and generally centrallyof said body, a lateral plate surrounding said nozzle and mountedthereon for movement generally axially Within said body, said nozzlehaving an outlet member generally adjacent the inner end of said nozzleand said body to discharge fuel inwardly of said plate in any operativeposition thereof, said plate having a planar face transverse to the axisof said nozzle, the operative peripheral edge of said plate being spaceda substantially uniform distance from the inside of said body in anyoperative position of said plate, said body having an inlet forcombustion air positioned axially outwardly of said member and saidplate, said body also having a portion of substantially constant crosssection axially coincident with every operative position of said plate,said body further being adapted to have substantially all of thecombustion air forced into said body outwardly of said plate, said platefurther being movable through a substantial distance range within saidbody between extreme operative positions, and limit means operable fromthe outside of said burner for adjustably moving said plate to hold itbetween said out- 6 let member and said combustion air inlet and withinsaid portion of substantially constant cross section in every operativeposition of said plate, whereby the farther that said plate ispositioned away from said member the more luminous and longer a flameproduced by said burner will be, and vice versa.

4. In combination, in a burner for fuel gas adapted to close a burneropening through a furnace enclosure, a tubular air body having agenerally straight portion extending to and defining the inner dischargeend of said burner, means for directing substantially all combustion airfor said burner into said body for axial inward flow therethrough, asubstantially annular transverse plate within said body having anoperative periphery in substantially uniform spaced relation to andwithin said portion in each relative operative position of said plate, afuel nozzle extending into said body along the axis thereof and throughsaid plate in adjoining relation thereto, said plate being shiftablethrough a substantial distance range along said nozzle and within saidbody, said nozzle having an inner end adjacent the inner end of saidbody for the discharge of fuel gas generally inwardly of each operativeposition of said plate, said inner end of said nozzle being axiallyoutwardly of the inner end of said body, and limit means to hold saidplate within said portion in a selected operative position relative tosaid inner end of said nozzle.

5. In combination, in a gaseous fuel burner adapted to close a burneropening through a furnace enclosure, a generally cylindrical air body,means for directing substantially all combustion air for said burner tothe outer end of said body for uniformly distributed entry thereinto, anannular plate within said body having a generally circular peripheraledge in substantially equidistant spaced relation to and within saidbody in each relative operative position of said plate, said body havinga substantially constant operative cross section portion inwardly ofeach relative operative position of said plate, a fuel nozzle extendinginto said body along the axis thereof and through the center of saidplate in shiftable fitted relation thereto, said plate being shiftablethrough a substantial distance range along said nozzle and within saidportion, limit means to prevent said plate being positioned inwardly ofsaid portion, said nozzle having an inner end adjacent the inner end ofsaid body with a plurality of outlet openings therein in spaced relationaround the axis of said nozzle for transverse discharge of at least aportion of the fuel therethrough generally inwardly of each operativeposition of said plate, and means operable from the outside of saidburner to selectively move said plate axially relative to the positionof said outlet openings and thereby vary the spacing thereof in saidbody outwardly from said inner end of said nozzle.

References Cited in the file of this patent UNITED STATES PATENTS1,344,029 Fisher June 22, 1920 1,844,315 Forney Feb. 9, 1932 1,857,697Scott May 10, 1932 1,976,208 Agthe et al. Oct. 9, 1934 2,055,366Schrader Sept. 22, 1936 2,124,175 Zink July 19, 1938 2,377,497 HopkinsJune 5, 1945 2,831,535 Lange Apr. 22, 1958 FOREIGN PATENTS 35,465 FranceAug. 26, 1929 611,776 Great Britain Nov. 3, 1948 OTHER REFERENCES TheLuminous Flame and Its Application; Heat Treating and Forging: April1939; pp. 200203 (copy in Class 158, subclass UNITED STATES PATENTOFFICE CERTIFICATE OF CORRECTION Patent No 3, I54, 134 October 27, 1964Frederick S. Bloom It is hereby certified that error a ppears in theabove numbered patent requiring correction and that the said LettersPatent should read as corrected below.

Column 1 line 14, for "and" read an column 4, line 59, for "in" read bySigned and sealed this 6th day of April 1965 (SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

3. IN COMBINATION, IN A BURNER FOR A GASEOUS FUEL, AN AXIALLY EXTENDINGTUBULAR BODY, A HOLLOW NOZZLE EXTENDING AXIALLY AND GENERALLY CENTRALLYOF SAID BODY A LATERAL PLATE SURROUNDING SAID NOZZLE AND MOUNTED THEREONFOR MOVEMENT GENERALLY AXIALLY WITHIN SAID BODY SAID NOZZLE HAVING ANOUTLET MEMBER GENERALLY ADJACENT THE INNER END OF SAID NOZZLE AND SAIDBODY TO DISCHARGE FUEL INWARDLY OF SAID PLATE IN ANY OPERATIVE POSITIONTHEREOF, SAID PLATE HAVING A PLANAR FACE TRANSVERSE TO THE AXIS OF SAIDNOZZLE, THE OPERATIVE PERIPHERAL EDGE OF SAID PLATE BEING SPACED ASUBSTANTIALLY UNIFORM DISTANCE FROM THE INSIDE OF SAID BODY IN ANYOPERATIVE POSITION OF SAID PLATE, SAID BODY HAVING AN INLET FORCOMBUSTION AIR POSITIONED AXIALLY OUTWARDLY OF SAID MEMBER AND SAIDPLATE, SAID BODY ALSO HAVING A PORTION OF SUBSTANTIALLY CONSTANT CROSS